From U.S. Pat. No. 2,756,738 there are known cooking apparatuses or kits of the above-mentioned type where the hot gas which is provided by the burner is caused to flow upwards between the burner and the bottom of the vessel and radially outwards therefrom along the bottom towards the lower portion of the casing. This lower portion of the casing deflects the gas there, thus causing it to flow up through the gap between the cooking vessel and the casing and out into the ambient open air through openings in the casing's upper portion. The object is thereby achieved that the heat energy in the gas is exploited to a great extent for heating the contents of the cooking vessel. However, the casing is made of a thin metal sheet and emits a large amount of heat radiation.
From the prior art it is also know that the casing is made of metal and has double walls which define an annular space wherein a heat-insulating material may be placed.
When using the cooking apparatus the object is thereby achieved that the temperature of the casing's outer surface may be low and that the casing emits only a small amount of heat radiation which may betray its position, a factor which can be important in military use of the cooking vessel, but the double metal walls cause the cooking apparatus to be relatively heavy. The lid closes the cooking vessel at the top.